Hundreds of police and security personnel were deployed around the court, where they clashed with demonstrators who want the activists released. At least four people were injured, as supporters attempted to break through police barricades near the court.

Von Pov and other activists are charged with inciting and committing violence during demonstrations in January. Ten of them were questioned for their roles in demonstrating outside the Yak Ching garment factory.

Von Pov, head of the Independent Democratic Association of Informal Economy, denied the charges against him under questioning Tuesday.

He had gone to the demonstrations as an observer and had not instigated or participated in any violence, he said.

He was severely beaten by members of Brigade 911, a special security unit, who hit him with steel pipes and threatened to kill him, Von Pov told the court.

The trial of the 23 activists have been heavily criticized by rights groups, who say they are being tried to discourage further demonstrations.

“I think it has gone too far to have justice for the 23 people…because the court has linked this issue to politics,” Am Sam Ath, lead investigator for the rights group Licadho, said.